Horizontal Axis Logarithmic Spiral Fluid Turbine

ABSTRACT

The present invention is a more simplified and efficient design of a turbine. The use of a logarithmic curve pattern for blade design and an aerodynamic profile allows the present invention to not only be versatile in its uses, but also much more efficient at gathering forms of energy for different purposes.

The current application claims a priority to the U.S. Provisional Patentapplication Ser. No. 61/387,894 filed on Sep. 29, 2010.

FIELD OF THE INVENTION

The present invention relates generally to turbine for the generation ofelectrical energy. More specifically, the present invention takes theshape of a logarithmic spiral with a horizontal axis for efficientrotation. The present invention relates to fluid rotors, also calledturbines, and pertains particularly to a rotor for flowing water, windand the like.

PRIOR ART

In the World International Patent Organization Application 2010043887A2,the process of attaining vortical flow is achieved using two componentsinvolving a turbine mounted to a duct with guide vanes to channel thefluid and change its direction and speed before contact with the saidturbine. Thus, the uniqueness and efficiency of this design lies in thepresence of the two components together. This turbine works only iffacing the fluid current direction. Also, the turbine blades do notspecify a logarithmic spiral.

In the U.S. Pat. No. 4,368,007, the introduced invention in one aspecthaving the blades mounted in a spiral shape around a central sphericallyshaped hub has the blades extending outward and facing forward. Thisforces the fluids to flow inward toward the axle after contact with theblades reducing the fluid velocity. The prior art has an enlargedcentral hub to force the fluid away from the rotary axle and increasevelocity before contact with the blades.

In the U.S. Pat. No. 7,344,353, the introduced invention consists of ahelical turbine mounted on a vertical axis and rotates horizontally. Itis mentioned that: “The blades position and shape are substantiallyunchanged as one move along the vertical axis”. Also, in vertical axisturbines, one surface of the blade is always facing the current andtorque is acquired through resistance rather than lift.

In the U.S. Pat. No. 7,494,315, the introduced invention is a turbinewith a helical shape as opposed to the logarithmic curve. The fluid flowfor this prior art is perpendicular to the vertical rotary axis.

In the U.S. Pat. No. 6,948,910, the introduced invention is aspiral-based axial flow devices consist of rigid spiral band catenariesaround an elongated profiled hub to be used in wind.

In the U.S. Pat. No. 7,728,454, the introduced invention includes agenerally helical turbine blade rotatable mounted on a central shaft,which may be tapered at each end, a flange extending perpendicularly toan edge of the turbine blade. This prior art is designed to work onlyunder water, does not follow the logarithmic spiral, and has a modifiedhelical shape blade with extra parts mounted in front and rear to helpself orienting the turbine into the fluid flow direction.

BACKGROUND OF THE INVENTION

The conversion of kinetic energy from flowing fluids, such as flowingwater or air, has been a significant source of power for many centuries.Various designs of wind mills and water mills exist today and are usedin many regions around the world for producing electric power from therotation of such turbines.

The rising cost and decreasing supply of fossil fuels creates aconsiderable need in harnessing renewable energy such as flowing windand water more efficiently. In prior arts, there have been manydifferent designs of wind mills and water mills all having variousbenefits but also disadvantages. For example, water mills that arecurrently used to generate electric power require a considerablequantity of strong water current to operate efficiently resulting in aneed to build costly damns and structures to control the water currentflow direction and speed. Presently, wind turbines not only compromise asignificant amount of their torque to acquire high speed, but alsorequire a relatively big space and in some cases, they may even behazardous. Also, they are known to be expensive to construct, maintain,and engineer.

Accordingly, it is desirable that safer turbines that can withstandhigher forces and generate equal or higher energy be available while notsubject to the problems of prior arts.

It is known that all fluids follow one common behavior when in motion,which is a logarithmic spiral. For example, turbulence, hurricanes, andwater flowing down the drain all follow a similar logarithmic spiralpattern. The present invention is intended to harness fluids based onthis concept of logarithmic spiraling. It may be similar to prior artslike the Archimedean screw, or the 1849 James Francis water turbine, andothers, but the present invention is intended to be an improvement inthis field.

SUMMARY OF THE INVENTION

It is accordingly the primary object of the present invention toovercome the above problems of the prior art.

An objective of the present invention is to provide an improved fluidturbine that is effective in generating more power in a given radius,fluid type, and velocity while at the same time is simple, safe, andinexpensive to construct and maintain.

In accordance with the primary aspect of the horizontal axis logarithmicspiral fluid turbine, otherwise known as a logarithmic turbine, includesa plurality of blades mounted symmetrically and curve along the axis ofrotation in a logarithmic spiral shape. Each blade consists of alogarithmic curve pattern with a certain curve radius and placed arounda rotary axis. The surface of the blade is perpendicular to the axisfrom each point on the spiral. Also, the surface of the blade may beconcave at the side of the blade facing the rotation direction in orderto give it an aerodynamic shape and increase lift.

One objective of the present invention is to guide the moving fluidaround the logarithmic turbine's rotary axle and between the blades in amanner to collect the fluid kinetic energy more efficiently than inprior arts.

The logarithmic turbine of the present invention is designed having arelatively smaller radius, slope, angle, and surface in the closestpoints of contact facing the current and increasing gradually accordingto the logarithmic spiral formula. The length of the logarithmic spiralis also the leading edge of the turbine, which is relatively longcompared with leading edges found in prior arts.

The rotary axis is attached to an electric power generator from eitherfront end or back end, which allows the logarithmic turbine to transferthe collected energy into usable power.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front plan view of another embodiment of the presentinvention mounted onto a tower.

FIG. 2 is a rear perspective view of another embodiment of the presentinvention mounted onto a tower.

FIG. 3 is a front plan view of the present invention of anotherembodiment tethered to a generator.

FIG. 4 is a front plan view of another embodiment of the presentinvention with a second cylindrical extension and mounted onto a tower.

FIG. 5 is a front plan view of the plurality of blades and the rotaryaxle of the present invention.

DETAIL DESCRIPTION OF THE INVENTION

All illustrations of the drawings are for the purpose of describingselected versions of the present invention and are not intended to limitthe scope of the present invention.

Of the many possible functions of the horizontal axis logarithmic spiralfluid turbine, otherwise known as a logarithmic turbine, one is totransform rotational energy into electric power by rotating an electricgenerator. This use demonstrates the ability to provide electricity thatcan be used for a variety of different uses. Another use for thelogarithmic turbine is for it to be installed on a fixed tower facingthe wind or water flow to generate electric power. It could have a selforientation mechanism to face the current if front is attached by apivoting bearing to a vertical tower. Also it may be installed on a fastmoving object to generate power from relative fluid flow. For example,the logarithmic turbine may be pulled behind a boat or mounted on avehicle to generate power when object is moving and as a result be ableto measure the current speeds of fluids. Other aspects that contributeto the uniqueness of the logarithmic turbine is involved with the designfeatures of different components of the present invention, whichcontribute to a better functioning and more efficient turbine.

In reference to FIG. 1 and FIG. 2, the most basic logarithmic turbinecomprises of a plurality of blades 1, a rotary axle 9, a firstcylindrical extension 10, a generator 18, and a hall 11. In the presentembodiment, each of the blades 1 comprise of a blade surface 2, a center3, a leading edge 4, a trailing edge 5, a curve radius 6, a logarithmiccurve pattern 7, and an aerodynamic profile 8. The blades 1 are mountedsymmetrically on a horizontal axis known as the rotary axle 9.Specifically the center 3 of the blades 1 is attached directly onto therotary axle 9. This ensures that the blades 1 are securely attached tothe rotary axle 9.

Unlike the typical vertical mounting of a turbine, the present inventionis mounted horizontally, which adds to its better functionality overprevious turbine designs. In traditional turbines, a vertical axis uponwhich the blades rest is perpendicular to the current of the fluid.Having a horizontal axis allows the axis to be parallel to the fluidcurrent, which can improve the efficiency of the logarithmic turbinebecause it does not have to work against the flow of fluid. This type ofhorizontal turbine set up can rotate faster than the fluid speed.However, the vertical axis turbines are known to have high torque but itis rather impossible for them to rotate faster than the fluid speed.

In reference to FIG. 1 and FIG. 2, the specified curve radius 6, whichis the distance between an edge of the blade 1 and the center 3, variesalong the rotary axle 9. The ratio of the overall spiral height to itsradius 6 may be determined according to desired use in terms of presentfluid density and velocity. The logarithmic turbine is unique becauseeach blade surface 2 has the configuration of the logarithmic curve 7,otherwise known in mathematics as an equiangular curve or as a goldencurve. Also, even though the turbine blades follow the logarithmic curve7, the radius 6 changes along the horizontal axis. The blades 1 curvegradually around the center 3 and outward in the logarithmic curvepattern 7 rather than having the same radius all along its rotary axle9. This manner of curving around the center 3 and rotary axle 9 allowsthe fluid to be pushed outward and around the rotary axle, forming avortex around the axle and expanding around the turbine. This aspect ofthe present invention causes the fluids passing inside the turbineclosest to the axle 9 to increase in velocity before exiting from therear because they have to travel a longer distance than surroundingfluids. In a traditional helix curve, the radius of the blade remainsconstant along the horizontal axis. The present turbine also createslift behind the blades to help increase the velocity at which the bladesare spinning Helical shape turbines rely more on pushing force, whichmake them slower.

Referring to FIG. 1, FIG. 2, and FIG. 5, the blades 1 have anaerodynamic profile 8 due to the logarithmic curve 7 it follows in whichthere is a smaller amount of exposed blade surfaces 2 in the front asopposed to the larger exposed blade surfaces 2 in the rear. Since theblades 1 are shaped to resemble an aerodynamic profile 8, the blades 1are narrow in the front and taper outwards, creating a larger rear, thusexposing more blade surface 2. Also, the blade surfaces 2, as a result,are concave when facing the direction of rotation 12. The aerodynamicprofile 8 will help to create a more efficient logarithmic turbinebecause of its ability to move the fluid in a more efficient manner byshifting excessive fluid to the larger blade surfaces 2 in the rear ofthe logarithmic turbine. Another advantage of having this aerodynamicprofile 8 of the turbine is simplicity and the low drag especially whentethered or pulled behind a moving object from its front part. Theaerodynamic profile 8 is also intended to help point the turbine toself-orient into the fluid current direction. This is achieved bymounting the front part of the turbine to a horizontal pivot point or toa cable, which will be later discussed.

Again, in reference to FIG. 1, FIG. 2, and FIG. 5, the aerodynamicprofile 8 and logarithmic curve pattern 7 of the blades 1 make thelogarithmic turbine appear as a cone rather than a disk (which is thecase for traditional turbines) when spinning at high velocities. Unlikeother turbines with a central hub in the middle, the leading edge 4 ofthe blades 1 in the front center of the apparatus is relatively parallelto fluid flow direction for better stability. Having the leading edge 4parallel to the flow direction of fluid will ensure that the logarithmicturbine is efficient in its functionality of gathering kinetic energy.The trailing edge 5 is perpendicular to the rotary axle 9 and has thelargest curve radius 6. Since the trailing edge 5 is at the rear of theblade 1, it is a part of the blade 1 that is has the most exposed bladesurface 2 and as a result, has the largest curve radius 6. At present,the logarithmic turbine uses lift behind the blades 1 in addition to apush force. Also, the present invention uses lift created from increasedfluid velocity passing inside the turbine relative to surroundingfluids.

Referring to FIG. 1 and FIG. 2, the first cylindrical extension 10, withthe hall 11 passing through its center from one side to the other, is aprotruded part that stems off the rotary axle 9. The first cylindricalextension 10 is mounted in front of the blades 1. This cylindricalextension 10 serves as a means to transfer the rotation and transform itinto other types of energy (such as electrical if attached to anelectric power generator).

In reference to FIG. 4, another variation of the present embodimentinvolves attaching another hollow cylindrical extension or insert. Thissecond cylindrical extension 17 is mounted on a rear side of theturbine. The placement of the second cylindrical extension 17 isintended so the generator 18 that will be used with the presentinvention may be placed from behind if desired.

In reference to FIG. 1, FIG. 2, and FIG. 3, the hall 11 in thecylindrical extension 10 serves two main purposes. One such purpose isto provide ample space to insert a screw to fix it to anothercylindrical extension with slightly larger radius. Also, another purposeis so there is space to pass a cable 16 through the hall 11 so theturbine can be tethered or attached to a generator 18. Both are vital inadding variation to the present invention.

Other variations of the present embodiment are a result from what objectit is attached to. One such variation is having the logarithmic turbineattached to a fixed pole or tower and using a self-orientating mean. Inreference to FIG. 1 and FIG. 2, a horizontal pivot component 14 part maybe used to mount the turbine and generator 18 along any height of a poleor on top of a tower such as a street light, or a boat mast to collectwind energy. The pivot component 14 will help the logarithmic turbine tospin and move as it sees fit depending on fluid flow. The generator 18and electrical parts may be placed on a deck 15 mounted on top of thepivot component 14. A support bar 13 is able to add an extra support forthe first cylindrical extension 10. The support bar 13 rests on top ofthe deck 15, closing the space between the deck 15 and the firstcylindrical extension 10. An axle of the generator 18 passes besides thefixed object (i.e. pole) and connects to the logarithmic turbine locatedon the opposite side. Placing the generator 18 and components on oneside and the logarithmic turbine on the other side creates enoughbalance needed to apply equal gravitational force on each side of thepivot ring. The pivot component 14 has bearings inside, which allows itto easily pivot horizontally around another smaller ring that is fixedto the pole, thus contributing to the manner in which the logarithmicturbine can self-orient itself horizontally in the fluid currentdirection. The ability to self-orient helps to optimize the purposes ofthe turbine.

Referring to FIG. 3, the next variation of the logarithmic turbine ishaving it fixed to a moving object, but not using any self-orientationmethods. The logarithmic turbine may be attached from its front or rearto an electric generator by the generator's 18 axle and mounted to avehicle with cables 16 in order to generate power from relative fluidflow. For example, the present invention could be mounted to an electriccar to generate electricity and recharge its batteries while the car istraveling. This is an important benefit because there are not manyplaces where an electric car may be recharged because the car itself isstill very unique. The variation of adding the present invention to amoving object adds to the versatility of the logarithmic turbine. Thisallows for multiple ways in which the logarithmic turbine may be usedand adds to the convenience of the apparatus.

In reference to FIG. 3, one other variation includes having theapparatus tethered, in other words, attaching a cable 16 through thehall 11 in the front part of the cylindrical extension 10. The turbinemay be placed in a current, or pulled behind a vehicle while thegenerator is placed on a fixed surface. When tethered, the material usedto construct the turbine is an important factor to control its verticalposition in relation to the generator, instead of using a poll or tower.Turbine may be constructed from light-weight material to be used incollecting hydrokinetic energy. While tethered to any fixed object underthe water surface such as the seabed, the logarithmic turbine is able tocollect hydrokinetic energy from jet stream, tidal waves, and similarmoving water currents. Also, the turbine may be constructed from heaviermaterial if tethered from a fixed object above the water such as a boat,or a bridge above the river.

In reference to FIG. 1 and FIG. 2, the logarithmic turbine functions asa regular turbine, regardless of what variation of the presentembodiment is being used. While the logarithmic turbine is mounted fromits front end, fluid current hits the logarithmic turbine on all bladesurfaces 2, the rear part of the blades 1 collect the most kineticenergy, thus pulling the whole logarithmic turbine and self orienting toface the correct fluid direction. The current is almost parallel to theblades' 1 smallest surface in the front part of the turbine. The blades1 direct the current gradually away from the center 3 of the logarithmicturbine (and blades 1) and around it as it moves towards the rearcreating a vortex.

Again, referring to FIG. 1 and FIG. 2, fluid current in contact with theleading edge 4 is channeled between the blades 1 while pushing on theblades 1 on one side and pulling on the other, in an increasing rate asthe surfaces 2 and angle of attack increase toward the rear. The leadingedge 4 of each blade 1 is the length of the entire spiral, which isconsiderably longer than a leading edge of a conventional turbine havingthe same radius.

The fluid current traveling through the logarithmic turbine is divertedgradually from its original straight flow direction into a spiral,causing it to travel a longer distance in a given time relative tofluids current surrounding the whole turbine. This causes the fluidinside the logarithmic turbine to increase velocity in order to meet thesurrounding flow at the same time while exiting. This increase in fluidvelocity inside the logarithmic turbine helps increasing the turbinevelocity.

In reference to FIG. 1 and FIG. 2, the construction material can bevaried depending on different design specifications. Many of thespecifications for the logarithmic turbine depend on the size of thelogarithmic turbine, but material has to be lightweight, sturdy, andwith a smooth surface, including, but not limited to any type ofplastic, metal, textile, carbon fiber, or any similar material. It mustbe built to withstand high forces. Materials include but are not limitedto fiberglass, sail, and light metal like aluminum, plastic, and acombination of materials or others with similar properties. When usedunder water, the logarithmic turbine may be a built in gel—like materialor water inflated to give it the same density as water so it almostfloats. The ability to have the logarithmic turbine float makes it movemore efficiently because gravitation forces will be insignificant. Whenintended to use the apparatus in light winded environments, the blades 1may be constructed using strong inflatable material to collect kineticenergy from wind. In stronger wind conditions, another way to tether theturbine is by constructing it as a kite making the blades fromlight-weight strong textile material. The advantages to using thetextile material is ease of storage for when the apparatus is not in useand ease of transportation. Also, the blades 1 may be constructed as onewhole piece rather than attaching multiple blades together depending onthe size, material used, cost, or structural strength needed.

In reference to FIG. 1 and FIG. 2, the logarithmic turbine design may bemodified depending on also the types of fluid and their respectivedensities and speeds. The number of blades 1 may be modified whilekeeping the same spiral shape around the axis, preferably in an evennumber of blades for better balance. The height and radius ratio of thelogarithmic spiral created by the design of the blades 1 may be modifiedto manipulate the rotation speed and torque. Number of spiral turns(essentially, the blades 1 curving around the rotary axle) and theirdistance from each other may vary in order to control the rotation speedand torque. The design of the present invention may also have differentcolors, sizes and shapes. It may also be modified in thickness, weight,and material used to withstand higher forces. Colors and drawings may beused to create a visual effect while the turbine is turning serving asdecoration in addition to generating power.

When compared to other turbines, the logarithmic turbine holds many moreadvantages. The present invention transforms kinetic energy evenly alongits blades surface and in a gradual manner. The narrow front of thedesign facing the fluid direction replaces the fixed nose found in priorart taking advantage of this area. The logarithmic turbine is able todistribute and channel the flowing fluid (thus stress) more evenlybetween the blades. Also, the logarithmic turbine's elongated leadingedge allows for a start-up speed that may be significantly lower thanother fluid turbines. Another benefit of the logarithmic turbine, is itsability to withstand higher forces because the total surface of theblades is distributed in a relatively smaller radius and may be built inone whole piece. Another advantage of the logarithmic turbine is that itis inexpensive. Because of its simplicity, very few parts are needed tobuild, less engineering is involved, and there are low maintenancecosts. Also, the logarithmic turbine produces minimal noise because ithas fewer moving parts, and turbulence is minimal. Another added benefitto the logarithmic turbine is that it is safer for birds and marine lifethan the traditional turbines and as a result, less hazardous thanconventional wind or water turbines.

Although the invention has been explained in relation to its preferredembodiment, it is to be understood that many other possiblemodifications and variations can be made without departing from thespirit and scope of the invention as hereinafter claimed.

1. A horizontal axis logarithmic spiral fluid turbine comprises, aplurality of blades; a rotary axle; a plurality of cylindricalextensions; a generator; a hall; each blade comprises of a bladesurface, a center, a leading edge, a trailing edge; each blade spiralingaround the rotary axle; and the center of each blade being attached tothe rotary axle.
 2. The horizontal axis logarithmic spiral fluid turbineas claimed in claim 1 comprises the first cylindrical extension beingmounted in front of the plurality of blades; the first cylindricalextension being protruded from the rotary axle; the second cylindricalextension being protruded opposite of the first cylindrical extension onthe rotary axle; the hall traversing through the second cylindricalextension; and the hall being connected to the generator.
 3. Thehorizontal axis logarithmic spiral fluid turbine as claimed in claim 1comprises, the leading edge being narrower than the trailing edge andtherefore creating an aerodynamic profile; the trailing edge beingperpendicular to the rotary axle; the blade surface being perpendicularto the rotary axle; and the blade surface having a spiral shape with alogarithmic profile.
 4. A horizontal axis logarithmic spiral fluidturbine comprises, a plurality of blades; a rotary axle; a cylindricalextension; a hall; a generator; a support bar; a deck; a horizontalpivot component; the support bar being attached to the deck; the deckbeing attached to the generator; the horizontal pivot component beingattached to the deck; each blade comprises of a blade surface, a center,a leading edge, a trailing edge; each blade spiraling around the rotaryaxle; and the center of each blade being attached to the rotary axle. 5.The horizontal axis logarithmic spiral fluid turbine as claimed in claim4 comprises, the cylindrical extension being mounted in front of theplurality of blades; the cylindrical extension being protruded from therotary axle; the cylindrical extension being attached to the generator;the hall traversing through the cylindrical extension; and the hallbeing connected to the generator.
 6. The horizontal axis logarithmicspiral fluid turbine as claimed in claim 4 comprises, the leading edgebeing narrower than the trailing edge and therefore creating anaerodynamic profile; the trailing edge being perpendicular to the rotaryaxle; the blade surface being perpendicular to the rotary axle; and theblade surface having a spiral shape with a logarithmic profile.
 7. Ahorizontal axis logarithmic spiral fluid turbine comprises, a pluralityof blades; a rotary axle; a cylindrical extension; a hall; a generator;a plurality of cables; each blade comprises of a blade surface, acenter, a leading edge, a trailing edge; each blade spiraling around therotary axle; and the center of each blade being attached to the rotaryaxle.
 8. The horizontal axis logarithmic spiral fluid turbine as claimedin claim 7 comprises, the cylindrical extension being mounted in frontof the plurality of blades; the cylindrical extension being protrudedfrom the rotary axle; the hall traversing through the cylindricalextension; the plurality of cables traversing through the hall; and theplurality of cables attaching to the generator.
 9. The horizontal axislogarithmic spiral fluid turbine as claimed in claim 7 comprises, theleading edge being narrower than the trailing edge and thereforecreating an aerodynamic profile; the trailing edge being perpendicularto the rotary axle; the blade surface being perpendicular to the rotaryaxle; and the blade surface having a spiral shape with a logarithmicprofile.